Fremont, CA: 5 Health Violations — 78/100 (2026)
5 ZIP codes · 5 water systems · Updated 2026-06-03
For households in Fremont, CA water data shows a consistently above-average safety picture.
How Fremont Compares
Data: EPA SDWIS Last verified: 2026-06-03
Water Quality Map: Fremont, CA
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Score Distribution
Safety grade breakdown for Fremont's 5 ZIP codes.
Key Facts for Fremont Residents
- Your city's water systems recorded 40 violations in the past 5 years.
- Average lead level: 0.0053 mg/L.
- Homes built before 1986: 68% — older plumbing may contain lead solder.
- Estimated remediation: $1,780 per household.
- CDC health risk index: 9.67.
Fremont's Water Providers
Multiple utilities divide Fremont, CA's water service — 3 leading providers among 5 on the federal register.
Overview
We track water quality and home safety data for 5 ZIP codes in Fremont, California (population ~228,520), covering 5 community water systems serving approximately 420,874 people region-wide.
5 of 5 ZIP codes (100%) have recorded EPA violations. 5 health-based violations documented.
Home Safety Score
Average Home Safety Score for Fremont: B (78/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Fremont water systems draw from: Groundwater, Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0053 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 2 (Moderate Risk)
- Zone 1 (High): 0 ZIP codes
- Zone 2 (Moderate): 5 ZIP codes
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Stage 1 DBP Rule | Treatment Technique | 36 | 5 |
| Stage 2 DBP Rule | Treatment Technique | 12 | 5 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 94536 | B | 8 | 1 | Alameda County Water District |
| 94537 | B | 8 | 1 | Alameda County Water District |
| 94538 | B | 8 | 1 | Alameda County Water District |
| 94539 | B | 8 | 1 | Alameda County Water District |
| 94555 | B | 8 | 1 | Alameda County Water District |
All ZIP Codes in Fremont
- 94536 [B] — 8 violations ⚠
- 94537 [B] — 8 violations ⚠
- 94538 [B] — 8 violations ⚠
- 94539 [B] — 8 violations ⚠
- 94555 [B] — 8 violations ⚠
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.
Fremont Community Health Snapshot
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
What's in Fremont's Water?
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
Fremont Infrastructure Age
With 68% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Pre-1986 plumbing is not a rare legacy case in Fremont — it's the dominant profile. The median build year of 1977 indicates a housing stock where lead-soldered copper joints are a common structural feature of residences across the city.
Over half of homes in Fremont were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
How Remediation Costs Compare in Fremont
For most homeowners in Fremont, the estimated cost of water and safety remediation represents a proportionally modest share of what properties are worth — placing this area in the lower tier of the remediation share scale.
Remediation costs in Fremont are relatively low compared to home values. The $870–$2,980 estimated range is a small fraction of median property value. Home values are 75% above the California average.
Fremont: Lead Risk & Vulnerable Populations
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
Despite citywide averages serving as the standard public reference point, those aggregates cannot resolve what is happening at one specific faucet — and where 68% of Fremont homes come from before the solder rule or where utility samples sit at or above the action mark, the gap between system data and faucet reality matters more than it does in lower-exposure communities. An in-home draw closes that gap, with certified filtration through retailer networks available where confirmed faucet results warrant additional measures.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Fremont: Flood History & Water Damage Risk
The NFIP claim record for Fremont — 15 filed incidents — reflects genuine, recurring flood exposure rather than an isolated event or two. When a community accumulates flood claims at this volume and carries 60% of its ZIP codes inside FEMA-designated zones, flood history starts to factor into water quality planning in ways it doesn't for lower-exposure areas. Flooding introduces specific contamination pathways — runoff overwhelming treatment facility intake, surface water infiltrating private wells, and pressure disruptions in distribution systems allowing backflow — all of which become more relevant as flood frequency increases.
Fremont has a moderate flood history with 15 FEMA claims averaging $3,372 per payout. 60% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$1,780</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
Deep Dive Reports
Detailed analysis for Fremont, CA